550
FZUS63 KMKX 121950
GLFLM

OPEN LAKE FORECAST for Lake Michigan
National Weather Service Milwaukee/Sullivan WI
250 PM CDT Sat Sep 12 2026

FOR WATERS BEYOND FIVE NAUTICAL MILES OF SHORE ON Lake Michigan.

Waves are provided as a range of significant wave heights, which
is the average of the highest 1/3 of the wave, along with the
average height of the highest 10% of the waves which will
occasionally be encountered.

.SYNOPSIS...

A cold front will move across Lake Michigan late this afternoon
with modest southwest winds shifting west northwest. Modest
northwest winds will then prevail tonight and Sunday until high
pressure around 30.3 inches moves across the lake late Sunday
night into Monday morning. Winds will increase and veer south-
southwest Monday night into Tuesday as low pressure around 29.4
inches develops over Manitoba. Gales appear likely during this
time frame. Periods of showers and thunderstorms will accompany
the developing low from as early as Monday evening into Tuesday.
Winds will trend northerly and weaken behind a cold front Tuesday
night into Wednesday.

LMZ261-362-364-366-563-565-567-868-130315-
Lake Michigan from Seul Choix Point to Rock Island Passage 5 NM
offshore to Mid Lake-
Lake Michigan South of a line from Seul Choix Point to the
Mackinac Bridge and north of a line from Charlevoix MI to South
Fox Island 5 NM offshore-
Lake Michigan from Charlevoix to Point Betsie MI 5 NM offshore to
Mid Lake-
Lake Michigan from Point Betsie to Manistee MI 5 NM offshore to
Mid Lake-
Lake Michigan from Rock Island Passage to Sturgeon Bay WI-
Lake Michigan from Sturgeon Bay to Two Rivers WI 5 NM offshore to
Mid Lake-
Lake Michigan from Two Rivers to Sheboygan WI 5 NM offshore to
Mid Lake-
Lake Michigan from Pentwater to Manistee MI 5 NM offshore to Mid
Lake-
250 PM CDT Sat Sep 12 2026

SHEBOYGAN WI TO PENTWATER MI NORTH...

.TONIGHT...Northwest winds 10 to 20 kt becoming north 15 to
25 kt, then becoming northwest 10 to 20 kt late. Waves 2 to 4 ft.
.SUNDAY...Northwest winds 10 to 20 kt increasing to 30 kt. Waves
3 to 5 ft.
.SUNDAY NIGHT...Northwest winds to 30 kt becoming north 10 to
15 kt. Waves 3 to 5 ft subsiding to 2 to 4 ft.
.MONDAY...Northeast winds 10 to 15 kt veering to south 15 to
25 kt in the afternoon. Waves 1 to 3 ft building to 3 to 5 ft.
.MONDAY NIGHT...South gales to 40 kt. Chance of showers in the
evening, then showers overnight. Waves 7 to 10 ft occasionally to
13 ft building to 10 to 14 ft occasionally to 18 ft.
.TUESDAY...Southwest gales to 40 kt diminishing to 30 kt in the
afternoon. Showers in the morning, then chance of showers in the
afternoon. Waves 10 to 14 ft occasionally to 18 ft subsiding to
7 to 10 ft occasionally to 13 ft.
.TUESDAY NIGHT...Northwest winds 15 to 25 kt becoming north 10 to
20 kt. Waves 4 to 6 ft occasionally to 8 ft subsiding to 1 to
3 ft.
.WEDNESDAY...Northeast winds 10 to 20 kt diminishing to 10 to
15 kt. Waves 1 to 3 ft.
.THURSDAY...Northeast winds 10 to 20 kt becoming north 15 to
25 kt. Chance of showers. Waves 1 to 3 ft.

$$

LMZ080-669-671-673-675-777-779-870-872-874-876-878-130315-
Lake Michigan from Michigan City IN to St. Joseph MI 5 NM
offshore to Mid Lake-
Lake Michigan from Sheboygan to Port Washington WI 5 NM offshore
to Mid Lake-
Lake Michigan from Port Washington to North Point Light WI 5 NM
offshore to Mid Lake-
Lake Michigan from North Point Light to Wind Point WI 5 NM
offshore to Mid Lake-
Lake Michigan from Wind Point WI to Winthrop Harbor IL 5 NM
offshore to Mid Lake-
Lake Michigan from Winthrop Harbor to Wilmette Harbor IL 5 NM
offshore to Mid Lake-
Lake Michigan from Wilmette Harbor IL to Michigan City IN 5 NM
offshore to Mid Lake-
Lake Michigan from Whitehall to Pentwater MI 5 NM offshore to Mid
Lake-
Lake Michigan from Grand Haven to Whitehall MI 5 NM offshore to
Mid Lake-
Lake Michigan from Holland to Grand Haven MI 5 NM offshore to Mid
Lake-
Lake Michigan from South Haven to Holland MI 5 NM offshore to Mid
Lake-
Lake Michigan from St. Joseph to South Haven MI 5 NM offshore to
Mid Lake-
250 PM CDT Sat Sep 12 2026

SHEBOYGAN WI TO PENTWATER MI SOUTH...

.TONIGHT...Northwest winds 10 to 20 kt becoming north. Waves 3 to
5 ft.
.SUNDAY...North winds 10 to 20 kt becoming northwest 15 to 25 kt.
Slight chance of showers in the afternoon. Waves 4 to 6 ft
occasionally to 8 ft.
.SUNDAY NIGHT...Northwest winds 10 to 20 kt becoming northeast
10 to 15 kt. Waves 3 to 5 ft subsiding to 2 to 4 ft.
.MONDAY...East winds 10 to 20 kt becoming southeast 15 to 25 kt.
Waves 1 to 3 ft building to 3 to 5 ft.
.MONDAY NIGHT...Southeast gales to 40 kt becoming south. Chance
of showers overnight. Waves 6 to 9 ft occasionally to 12 ft
building to 10 to 14 ft occasionally to 18 ft.
.TUESDAY...Southwest gales to 35 kt diminishing to 30 kt. Showers
likely in the morning, then chance of showers in the afternoon.
Waves 10 to 14 ft occasionally to 18 ft subsiding to 6 to 9 ft
occasionally to 12 ft.
.TUESDAY NIGHT...Northwest winds 10 to 15 kt becoming north 10 to
20 kt. Chance of showers and thunderstorms. Waves 3 to 5 ft
subsiding to 1 to 3 ft.
.WEDNESDAY...Northeast winds 10 to 20 kt diminishing to 10 to
15 kt. Chance of showers. Waves 2 to 4 ft.
.THURSDAY...Northeast winds 10 to 20 kt becoming north 15 to
25 kt. Waves 3 to 5 ft.

$$

LMZ761-130315-
MAFOR 1222/
MICHIGAN NORTH 11720 11730 11830 11720 11710 11720 12730. Waves 2
to 4 feet subsiding to 1 to 3 feet tonight. Waves 1 to 3 feet
building to 2 to 4 feet Sunday.

MICHIGAN SOUTH 11610 12730 13820 12730. Waves 1 to 3 feet
building to 2 to 4 feet tonight. Waves 2 to 4 feet building to 3
to 5 feet Sunday.

$$


Gehring

Experimental modernized open lake forecast is available online at
weather.gov/mkx/glftable

Graphical marine forecasts are available online at:
weather.gov/greatlakes